Method and device for avoiding seed-metering errors in planters

ABSTRACT

The present invention patent relates to a solution for avoiding errors during the seed-metering process in planters, and comprises the following six steps: autonomous electricity generation to power the monitoring system; monitoring the seed charge in the metering disk (pre-sensor); monitoring the clogging of the metering disk by seeds (post-sensor); monitoring obstructions in the seed duct (post-sensor); processing the monitoring data; transmitting the processed data wirelessly to the central monitoring unit for follow-up and decision-making by the operator. One of the aims of the present invention patent is that of providing a solution for avoiding errors during the seed-metering process in planters, allowing the operator of the machine to be automatically alerted immediately after the error occurs, and also for permanently monitoring the quality of the planting process by means of a wireless data transmission system powered by an autonomous electric unit, dispensing with external batteries and power cables.

FIELD OF THE INVENTION

The instant patent of invention relates to a process and respective device for avoiding seed-measuring errors in planters and seeders, hereinafter referred to as planters, developed to provide an increase of efficiency of the planting process of agricultural seeds.

BACKGROUND OF THE INVENTION

It is well-known that the quality and efficiency of the planting process of grains strongly depend on the precision and uniformity of the seed-metering process, aiming to minimize population differences and the spacing between the plants.

The prior art contemplates planters with different types of metering disks and passage sensors, such as optical sensors, inter alia.

One of the prior art drawbacks lies in the presence of quite frequent errors due to the misuse of metering disks, to the unsuitable choice of disks or incorrect calibrations associated with seeds to be planted, depending on product malfunctioning or even on the frequent obstruction in seed ducts.

In order to prevent these types of planting errors, several types of passage sensors have been used in the monitoring process of seed metering. It appears that, in most situations, these sensors are placed in the seed duct itself, being subject to all kind of exposure associated with the hostile agricultural environment such as mud, water, dust, vibration and mechanical shock, in addition to the difficulties and possible imprecisions in seed counting.

Another prior art drawback relates to the frequent need for constructive adjustments in the duct, compromising the efficiency of seed flow through the duct.

Furthermore, the need for data transmission and electricity implies the installation of extra wires and batteries that are also subject to hostile field conditions, requiring constant maintenance and making the installation of the monitoring system difficult.

In this seed-metering monitoring process the timely alert to the equipment operator is critical to allow the quick correction of the root cause associated with the planting error and resume as soon as the normal operation of the planter.

One of the objectives of the instant invention is that of providing a solution for the control of errors in seed-metering process in planters, allowing the equipment operator to receive an automatic alert immediately at the time of the error as well as allowing the permanent monitoring of the quality of the planting process by means of a wireless data transmission system, powered by an autonomous central electric unit, eliminating the need for external batteries and power wires.

Therefore, in order to better illustrate the subject matter in question, a detailed description thereof with reference to the figures below will follow, where:

FIG. 1 shows the details of the steps of the process for avoiding seed-metering errors in planters.

FIG. 2 shows a perspective view of the fully assembled metering-equipment, where its main components can be identified.

FIG. 3 shows a front view of the fully assembled metering-equipment, where its main components can be identified.

FIG. 4 shows a side view of the fully assembled metering-equipment, where its main components can be identified.

FIG. 5 shows a perspective view of the metering-equipment without its protective lid, where its main components can be identified.

FIG. 6 shows a front view of the metering-equipment without its protective lid, where its main components can be identified.

FIG. 7 shows a side view of the equipment without its protective lid, where its main components can be identified.

FIG. 8 shows an exploded view of the equipment without its protective lid, where its main components can be identified.

FIG. 9 shows a perspective view of the fully assembled set of sensors, where its final arrangement can be visualized.

FIG. 10 shows a perspective view of the set of sensors with transparent protective cover, where its main components can be identified.

FIG. 11 shows a side view of the assemblage of the set of emitters and optical receivers, where the main components of the pre-sensor can be identified.

FIG. 12 shows a side view of the assemblage of the set of laser receivers and emitter, where the components of the post-sensor can be identified.

FIG. 13 shows an exploded view of the set of sensors without its protective lid, where its main components can be identified.

FIG. 14 shows a perspective view of the fully assembled set of sensors, where its final arrangement may be visualized.

FIG. 15 shows an exploded view of the set of dynamo where its main components can be identified.

FIG. 16 shows the logic architecture of the sensing equipment.

FIG. 17 shows the topology of a network of equipment and the respective data rows.

FIG. 18 shows the logic architecture of the operator's monitoring unit.

FIG. 19 shows a schematic front view of the set comprised by the distributing disk and the seed duct, where the sensors are placed before (pre-sensors) and after (post-sensors) seed drop.

FIG. 20 shows a schematic top view of the set comprised by the distributing disk and the seed duct, where the sensors are placed before (pre-sensors) and after (post-sensors) seed drop.

FIG. 21 shows a schematic side view of the set of pre-sensors, illustrating the functioning of the process for detecting seeds on the distributing disk, highlighting the absence of light reflection due to the absence of seeds on the disk.

FIG. 22 shows a schematic side view of the set of pre-sensors, illustrating the functioning of the process for detecting seeds on the distributing disk, highlighting the occurrence of light reflection due to the presence of seeds on the disk.

FIG. 23 shows a schematic side view of the set of post-sensors, illustrating the functioning of the process for detecting the obstruction in the seed duct, highlighting the absence of light reflection due to duct clearance.

FIG. 24 shows a schematic side view of the set of post-sensors, illustrating the functioning of the process for detecting the obstruction in the seed duct, highlighting the occurrence of light reflection due to duct obstruction.

According to the foregoing figures, the instant invention relates to an inspection equipment placed in a metering disk as shown in FIG. 2, capable of counting the dispensed seeds, detecting errors due to the absence of the seed in the holes of the distributing disk (7), detecting seeds stuck in the holes of the distributing disk (7) and detect obstruction in the seed conduct (10).

The inspection equipment consists of two proximity sensors placed before the seed drop (13) in the duct (10), a pre-sensor (1) and a post-sensor (2), which generate different analog voltage levels. These voltage levels that reaches the electronic board (3) are digitized by analog/digital converters (3.2) and delivered to the processor (3.1) as numerical data.

The numerical data are analyzed by an algorithm contained in a firmware embedded in the processor. Following this analysis, the information is delivered by means of a RF transceiver (3.3) to a central unit (8) placed in the operator's vision field.

The pre-sensor is a transducer whose output voltage is proportional to its distance from any protective screen. Thereby, it can be an optical emitter-receiver pair, an ultrasonic, or microwave, or capacitive proximity sensor or any other type of proximity sensor. The instant invention, as understood by FIG. 11, uses a narrow-beam infrared emitter (1.1) and an optical receiver (1.2) sensitive to the same wavelength. The receiver output voltage will be proportional to the light observed after being emitted by the emitter and reflected by some screen.

Given that the sensor is placed before the seed dropping region, the output voltage level will behave quite differently depending on whether the disk hole contains or not a seed since when the seed is absent light reflection does not occur, as understood by FIG. 21; while, when the seed is present light is reflected at least slightly, as understood by FIG. 22. Therefore, seeds and errors can be detected and counted through the algorithm.

The post-sensor (2) is a transducer similar to the pre-sensor (1), however it has a greater detection range. This greater range was obtained by replacing the narrow-beam infrared emitter by a more powerful collimated laser beam (2.1), as understood by FIG. 12. Furthermore, it has at least two optical receivers (2.2) to display enhanced sensitivity to reflected light and thereby enable the detection of a distant sensor screen. This sensor can be replaced or work together with ultrasonic or microwave sensors without losing the generality of the solution.

Such an optical arrangement makes possible to emit the light beam inside the seed duct, as shown in FIG. 23, and the presence of any screen will cause the partial reflection of the incident light, captured by the receivers, as shown in FIG. 24, resulting in a change of the output voltage level thereof. Therefore, the algorithm can both count the seeds stuck in the metering disk and detect seed duct obstructions.

The constructive arrangement proposed and shown in the figures relates to the application of the equipment in conventional metering disks, where the seeds are dispensed by gravity. However, this very inspection equipment can also be installed in pneumatic metering disks, by repositioning the pre-sensor upstream of the negative pressure region and by repositioning the post-sensor in the duct outlet to detect operational errors such as duct obstruction, absence or double distribution of seeds, when more than a seed is distributed at a time.

Another object of the instant invention is the system supplying the electricity required for the operation of the sensors and the other electronic components of the equipment. This system consists of a generator (6), an electricity accumulator (4) and a regulated source of power (3.4).

The generator can be any transducer capable of capturing energy from the environment and transforming it into electricity. In this invention we used a dynamo (6) that captures the rotational movement of the shaft of the metering disks by means of a set of gears (5) that amplify its rotation, together with a photovoltaic panel capable of capturing energy from sun light and turning it into electricity.

The accumulator is a device capable of storing electricity for long periods of time and providing it to the electronic board, wherein it can consist of an array of either researchable batteries or capacitors.

In the presence of sun light, the photovoltaic panel produces electricity that is transmitted to the electronic board by means of electric wires. The same occurs with the dynamo upon rotation of the metering disks.

In the electronic board, the power supply regulates and stabilizes the voltage to charge the accumulator and supply the electronic circuits. If no energy is supplied by the generator set, the voltage accumulator directly supplies the circuits.

The communication between the equipment and the central unit (8) takes place by radiofrequency, that is, wirelessly. To this end, the electronic boards of the equipment and of the central unit (8) are provided with transceivers RF (3.3), namely, electronic devices that receive data packets and send information via electromagnetic waves at a demodulation of received electromagnetic waves and the corresponding extraction of data packets.

In the instant invention communication is half-duplex (emitter and receiver alternate in the channel), ensuring packet delivery, power of 0 dBm in data transmission and −94 dBm in data reception. Frequency modulation is of the GFSK type (Gaussian frequency-shift keying), has a communication speed of 250 kbps, and a theoretical range up to 100 m in the open space.

The modulation base frequency is 2.4 GHz, suitable for transmissions of this nature to provide more robustness to noise.

In order to avoid interference between different networks, a process has been developed to determine the transmission frequency according to the physical address of each central monitoring unit. Thereby, for each one of the networks consisting of one central unit with several pieces of inspection equipment, the transmission frequency increases of 10 MHz, according to the address of the respective central unit. For instance, in network 1 the central unit address is 1 and the modulation frequency is 2.41 GHz (2.4GHz+10 MHz), while in network 2 the modulation frequency is 2.42 GHz (2.4 GHz+20 MHz), and so on.

Thereby, two different networks, for instance, two planters, can operate in the same space without interference between the two equipment networks.

To ensure the quality of data transmission between the equipment and the central unit (8), an algorithm was included for the consistency test and the respective transmission of the confirmation signal from the central unit (8) to the equipment—

Upon arrival at the central unit, the packets are handled serially and several actions are triggered therefrom. Any delay in this process may involve loss of a subsequent packet, for instance, sent by another device, decreasing network efficiency.

In order to obtain a highly efficient network, a row management system that optimizes the package receipt was developed.

The central unit has six input data rows, where

each row has three FIFO (First-In-First-Out) packet buffers, implemented in a star topology (1 central unit for 6 equipment families).

The pieces of equipment are evenly distributed in the rows of their physical address, as shown in FIG. 17.

The number of a row depends on the physical address of the respective equipment, according to the following algorithm:

row Number=Physical Address MODULE 6

Therefore, row number is determined by the rest of the division of the physical address by six. For instance, if the physical address of the equipment corresponds to number 32, the row of the respective equipment will be equivalent to number 2, corresponding to the rest of the division of 32 by 6.

In the event of a critical situation, for instance, the obstruction of the duct, an alert signal is immediately sent to the central unit by the equipment processor by means of the RF transceiver. The central unit (8) receives the signal with the information and displays a warning to the operator via GUI (9), triggering an audible alarm through the loud-speaker (12).

Furthermore, within regular time intervals, the equipment processor transmits to the central monitoring unit some non-critical information, such as the number of distributed seeds as well as the errors detected in a given time interval. The central unit crosses this information with the time and geographical position data provided by a GPS (11), displaying the results in its GUI (9).

In some cases the equipment can infer that the seed metering disk is not in use, as in the absence of a response during a communication with the central unit or when the electronic board is not powered by the generator for long periods of time, meaning that the metering disk is not being driven and, thus, there is the need for inspection by the sensor.

In these cases the equipment can perform energy saving functions, such as shutdown of the sensors and A/D converters as well as decrease of the processor clock, providing a reduction of energy consumption. 

1. A process for avoiding seed-metering errors in planters, wherein the process comprises the following steps: generating electric power in a metering disk by means of a dynamo; monitoring the seed charge directly in the distribution disk of seeds by means of a pre-sensor; monitoring the clogging of the seeds in the distribution disk of seeds by means of a post-sensor; monitoring obstructions in the seed duct by means of a post-sensor; detecting analog signals voltage generates by means of pre-sensor and post-sensor; converting the analog signals into digital signals using analog/digital converters; processing the digital signals on a processor; transmitting the processed digital signals to the central monitoring unit by means of a transceivers RF.
 2. A process for avoiding seed-metering errors in planters, according to claim 1, wherein the process uses a star network topology having a different data transmission frequency for each one of the networks consisting of a central monitoring unit.
 3. A process for avoiding seed-metering errors in planters, according to claim 2, wherein the process further uses a rows system, containing 3 buffers for each row, the row number being determined based on the physical address of the respective monitored equipment.
 4. A process for avoiding seed-metering errors in planters, according to claim 1, wherein the process is applied in pneumatic metering disk.
 5. A device for avoiding seed-metering errors in planters, wherein it is disposed into a metering disk of a planter, the device comprising: a pre-sensor having a narrow-beam infrared emitter and an optical receiver; a post-sensor having a collimated laser beam emitter and a least two optical receivers; a dynamo connected to the shaft of the metering disk that captures the rotational movement of the shaft by means of a set of gears; an electricity accumulator; and an electronic board having a signal processor, analog/digital converters and a transceivers RF; wherein the pre-sensor and post-sensor are disposed close to the distributing disk of seeds.
 6. A device for avoiding seed-metering errors in planters, according to claim 5, wherein the pre-sensor and post-sensor are sensors that consists of the group of ultrasonic sensor, microwave sensor, capacitive sensor or proximity sensor.
 7. A device for avoiding seed-metering errors in planters, according to claim 5, wherein the dynamo is used together with a photovoltaic panel.
 8. A device for avoiding seed-metering errors in planters, according to claim 5, wherein it is used in pneumatic metering disk by repositioning the pre-sensor upstream of the negative pressure region and by repositioning the post-sensor in the duct outlet of the metering disk. 